The invention relates to data-recording on photographic film, in direct association with a photographic exposure to which the data apply.
The desirability of data-recording in conjunction with photographic exposures has long been recognized, and the utility of light-emitting diodes (LED) for generation of data displays has also been recognized. Hoerenz, et al., U.S. Pat. No. 3,827,070 discloses such structure in application to the removable back of an otherwise conventional 35-mm camera, but the Hoerenz, et al. device has undesirable limitations, due to the fact that use of the LED devices is limited by the conventional refracting-optical elements needed to image multiple LED elements in desired array at the film surface. As a result, associated data-generating, data-display, and optical-imaging components require relatively great housing volume (bulk), and the number of digits which can be conveniently displayed at the film surface at any given time is relatively small. It goes without saying that the fewer the displayable digit positions at the film, the more limited is the capacity to record, for any given exposure. And in 35-mm film applications, the requisite bulk of prior data-recording devices has severely limited or foreclosed normal eye-level use of the viewfinder through which lens-focusing, subject-matter framing, and aperture-setting functions are performed.